Adjunction in Arabic, Case and Chain Theory

In this thesis, I investigate constructions involving adjunction in Arabic within the theory of Principles and Parameters as synthesized in Chomsky (1981) and further developed in subsequent work.;Constructions involving adjunction are structures in which an NP bears a government relation to a head to which it bears no thematic relation. They include Left-dislocation, Wh-questions, Topicalization, Exceptional Case-marking, and Non-thematic Subjects. Important principles of Universal Grammar appear to be violated in these constructions. Modifications and extensions are thus required to accommodate these constructions.;The theta-Criterion which requires every A-position to be assigned a O- role and every theta-position to be assigned an argument appears to be violated in Non-thematic Subjects. Since the subject A-position is generated at D-structure by the Projection Principle, that position must be a theta-position by the theta-Criterion. My resolution to this paradox is to reduce the first clause of the theta-Criterion to the Principle of Full Interpretation (FI), and propose a less restrictive notion of D-structure.;Case theory and the Visibility Hypothesis appear to be violated in the other constructions where an NP in an a-position must be Case-marked contrary to the predictions of the theory. I extend the domain of Case requirement to include such positions as well, and reinstate Case as a condition on interpretability that makes all NPs visible not to the theta-Citerion as standardly assumed but to FI. Given adjoined NPs with Case, the domain of Case theory is not only A-positions, but rather a-positions as well. Case and FI thus become intertwined facets of interpretability.;I propose that the direction of Case-marking for all lexical and non-lexical categories in Arabic is uniformly rightward, corresponding to the head-initial parameter of X¯-theory. Although Arabic clauses are uniformly verb-initial at S-structure, I argue that the verb originates in VP at D-structure, and moves out of VP to COMP in the mapping from D-structure to S-structure. Thus, nominative, accusative and genitive Case are assigned by a head to its complement only when the head precedes its complement. Assuming that V-movement must obey the Head Movement Constraint, the verb first must raise to the intermediate head position in inflection; then the verb plus inflection moves together to comp. This derives the surface constituent VSO order of Arabic.